While waiting for my wife today, I decided to listen to Bob Brinker on the radio, later it got a bit chilly (65 degrees F) so I turned on the heater. I found that if I just fully power up, instead of using accessory mode, the Prius ICE runs from time to time to charge the HV and this in turn keeps the 12 volt battery in a fully charged state possibly indefinitely. For emergency stranded situations ( in remote area ) this could be a life saving procedure as the ICE runs infrequently (eliminating the CO danger) and with even just half a tank of gas one could stay warm for 1-2 days. It is possible to monitor the SOC of both the HV and the 12V battery on the multi-display. Now if it just had a WC!
I do that frequently as I play taxi driver for the wifes errands on Saturday. At 20 degrees it comes on more frequently than you experienced, and you can watch the MPG head downward each time the ICE comes on. But as you say, it'll run the car for a VERY long time.
AGREE on all aspects, I sorely miss my 29 below episodes I experienced in Wisconsin. Californians are deprived.
